|Publication number||US7845441 B2|
|Application number||US 11/510,932|
|Publication date||Dec 7, 2010|
|Filing date||Aug 28, 2006|
|Priority date||Jan 20, 2004|
|Also published as||US7163213, US20050155799, US20070007051, WO2005070029A2, WO2005070029A3|
|Publication number||11510932, 510932, US 7845441 B2, US 7845441B2, US-B2-7845441, US7845441 B2, US7845441B2|
|Inventors||Steven J. Chambers|
|Original Assignee||Chambers Steven J|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (26), Referenced by (5), Classifications (17), Legal Events (3)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present application is a Continuation in Part of U.S. patent application Ser. No. 10/761,089, filed Jan. 20, 2004 now U.S. Pat. No. 7,632,213, which application is incorporated herein by reference.
The present invention relates to a powered carrier, and more particularly to controls for a powered hand truck.
Hand trucks (or dollies) are well known and commonly used both residentially and commercially to move objects from place to place. Many improvements have been made over recent years to improve hand trucks, and current models provide quality and convenience. However, due to the geometry of basic hand trucks, they are limited to carrying objects of limited dimensions. Convertible hand trucks having four wheels have been developed which are able to carry objects too bulky for two wheel hand trucks.
Because of the high quality built into many hand trucks, they may be used to move very heavy objects. While these qualities have expanded the utility of hand trucks, the ability to carry heavy objects has also created greater weights for operators to deal with. Such heavy weight has created a need for some form of power assistance for hand truck operators. However, in order to retain the utility of the hand truck, the powered hand truck must have weight and dimensions similar to the prior art hand truck. Additionally, the powered hand truck must be controllable in a safe manner, and must allow manual use of the powered hand truck in the event that the power unit fails. Because there are many prior art hand trucks in use, there is a further need to easily convert manual hand trucks to powered hand trucks.
A powered hand truck resolving the above mentioned problems is described in U.S. patent application Ser. No. 10/761,089, filed Jan. 20, 2004 by the present Applicant. The '089 application describes a powered hand truck and a kit for converting a manual hand truck to a powered hand truck. The powered hand truck of the '089 application includes a speed control located on or near a handle used to steer the hand truck. Both a wired speed control and a wireless speed control are described therein. While the '089 application discloses many useful features for a powered hand truck, control improvements remain which may improve the control and safety of powered hand trucks.
The present invention addresses the above and other needs by providing an advanced control for a powered hand truck. The powered hand truck includes an electric motor, a power source, a programable motor controller, and a transaxle, which are adaptable to existing hand trucks, or may be integrated into a new powered hand truck. The motor controller controls the motor to provide consistent speed independent of load weight or incline, and further provides regenerative braking. The advanced control may be wired or wireless and provides a touch sensitive circuit to command stop if the operator is not holding the handle, and an electronic potentiometer. The wireless control further includes a unique code for validating speed commands and initiates deceleration if the control signal is lost.
In accordance with one aspect of the invention, there is provided a wirelessly controlled powered hand truck. The powered hand truck includes a hand truck frame and a handle for steering the hand truck. An electric motor provides power for the hand truck and a transaxle driven by the electric motor has differentially connected right and left axles with right and left wheels attached to the right and left axles respectively. A power source provides electrical power for the motor and a motor controller controls the electrical power provided to the motor. A wireless control circuit includes a transmitter circuit and a receiver circuit. The transmitter circuit includes a first processor, an operator actuated speed control attached to the handle and generating a speed control command provided to the first processor, and at least one touch point residing proximal to the speed control at a location graspable by the operator during normal hand truck operation. The touch point generates a touch point signal provided to the first processor and a radio transmitter receiving a wireless speed control signal from the first processor and transmits the wireless speed control signal. The receiver circuit includes a second processor and a radio receiver which receives the wireless speed control signal and provides the wireless control signal to the second processor. An electronic potentiometer receives a potentiometer control signal generated by the second processor based on the wireless speed control signal and provides a motor controller speed command to the motor controller. The motor controller speed command is decreased if the touch point signal indicates that the operator is not touching at least one of the touch points.
The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims.
The present invention is a kit for powering hand trucks, and for powering convertible hand trucks in particular. The kit may be adapted to new hand trucks, used hand trucks, or may be incorporated into the initial manufacturing of hand trucks. The kit is particularly suitable for conversion of the Gemini® Jr. and Gemini® Sr. and similar hand trucks, for example, hand trucks manufactured by Harper Hand Trucks in Wichita, Kans. and by Cascade Equipment, to powered hand trucks, for assisting in the movement of objects.
An example of a powered convertible hand truck is shown in
The powering assembly 34 is attached to the side plates 38 and back plate 37. A top view of the side plates 38 and back plate 37 is shown in
A side plate insert 38 a held in place by side plate insert fasteners 39 is shown in
The internal components of the powering assembly 34 are shown in
The transaxle 40 preferably is geared between sixteen to one and twenty five to one, and more preferably twenty one to one. The transaxle 40 is preferably between approximately sixteen inches and twenty three inches wide, and more preferably between approximately nineteen inches and approximately twenty two inches wide, and most preferably approximately 19.3 inches wide (where width is defined as from right axle tip to left axle tip). The transaxle 40 is preferably a limited slip transaxle. A preferred transaxle is reference number S23083, made by Stature Electric in Watertown, N.Y.
The motor 42 is preferably between approximately one quarter and approximately one half Horse Power (HP), and more preferably between approximately one quarter and approximately one third HP, and most preferably approximately one quarter HP. The motor 42 is further preferably an approximately twelve volt motor to an approximately thirty six volt motor, and more preferably an approximately twenty four volt motor. The motor 42 diameter is preferably between approximately three inches and approximately five inches, and is more preferably approximately three and one half inches. The motor 42 is oriented relative to the transaxle to provide maximum ground clearance without interfering with other powering assembly 34 components. Preferably motors are manufactured by Stature Electric in Watertown, N.Y., and by Euclid/Imperial Electric in Akron, Ohio. A manual brake is integrated into the motor 42 and is activated by a lever 43 extending rearwardly from the right rear of the motor 42.
The motor controller 44 preferably is a programable motor controller and controls the motor 42 to maintain a desired speed independent of load and/or incline. The motor controller 44 also provides regenerative braking. Programs may be saved by the motor controller 44 and downloaded into the motor controller 44. The motor controller 44 is switchable between low and high speeds, and the low speed and high speed may be programmed, acceleration may be programmed, and braking may be programmed. Active (i.e., using the motor 42) braking is also provided by the motor controller 44, wherein the hand truck speed is limited to a desired speed when the hand truck is descending an incline. The motor controller 44 is preferably an Off The Shelf (OTS) motor controller and is more preferably an i-Drive, made by PG Drives in Dorset, UK.
The power source 46 is preferably twelve volt, twenty four volt, or thirty six volt and preferably replaceable and/or rechargeable batteries, and more preferably two twelve volt batteries in series providing a total of twenty four volts and 7.2 amp-hr, and most preferably are two approximately six pound approximately 2.55 inch wide by approximately 3.75 inch high by approximately 6.00 inch length batteries. The batteries may be lead acid, lithium, nickel metal hydride, or nickel cadmium batteries. Advantageously, using two twelve volt batteries allows recharging from many common sources such as an automotive electrical system. The batteries preferably reside in series behind hinged access doors in a battery compartment, with central springs biasing the batteries outward for easy removal. Power source 46 voltage is displayed by voltage display 56 above the power source door 58 (
The charger 48 is preferably a twenty four volt universal charger, and preferably a smart charger wherein, for example, the charger 48 charges at full charging rate until ninety percent of full charge is reached, and then the charger 48 switches to a trickle mode. A preferred charger is manufactured by Soniel in Canada.
A controller display 50 and on/off switch 51 reside above a right power source door 56 shown in
A detained view of the handle 26 (generally the right handle) is shown in
The low speed is generally suitable for using the hand truck in a two wheel mode, and the high speed is generally suitable for using the hand truck in a four wheel mode. Additionally, an additional high speed lockout may be built into the latch receiving member (see
The optional hi/low speed switch 36 a selects one of two speeds programmed into the motor controller 44. The optional on/off switch 36 b provides the same function as the on/off switch 51 (see
The speed control 36, the hi/low speed switch 36 a, the optional on/off switch 36 b, and the indicator 33 may also be mounted on a separate box throttle 52 as shown in
A block diagram of a wireless control system 72 according to the present invention for the powered hand truck is shown in
A radio receiver 88 receives the transmitted signal 71 and provides the wireless speed control signal 67 to a second processor 92. A voltage regulator 90 provides a regulated power signal 91 to the processor 92. The processor 92 processes the wireless speed control signal 67 as described in
A wireless control transmitter circuit 60 according to the present invention for the powered hand truck is shown in
Touch points 62 are electrically connected to a timer 64. The timer 64 is a touch detection device. When the operator touches the handle 26 or box throttle 52, the timer 64 detects the presence of the operator and sends a touch signal to the processor 66. If the operator is not touching the handle 26 or the box throttle 52, then after a short period of time, preferably approximately ¾ seconds, the touch signal switches from HIGH (enable speed) to LOW (disable speed) and the processor initiates a gradual deceleration (see
The radio transmitter 70 may be, for example, a Parallax 433 MHz RF Transmitter model number 27980 made by Parallax, Inc. in Rocklin, Calif., or a similar transmitter. The processor 66 may be, for example, a basic stamp processor, and is preferably a BS2PX24 made by Parallax, Inc. in Rocklin, Calif. The timer 64 may be, for example, a Fairchild NE555 made by Fairchild Semiconductor in South Portland, Me. Parameters for the remaining transmitter circuit elements are shown in Table 1.
Transmitter Circuit Elements
0.01 uF 10 V
0.1 uF 10 V
0.15 uF 10 V
20 M ⅛ W
100K ⅛ W
220 Ohm ⅛ W
+5 Volts DC
A wireless control receiver circuit 80 according to the present invention for the powered hand truck is shown in
The receiver may be, for example, a Parallax 433 MHz RF Receiver model number 27981 made by Parallax, Inc. in Rocklin, Calif., or a similar receiver. Parameters for the remaining receiver circuit elements are shown in Table 2.
Receiver Circuit Elements
0.1 uF 10 VDC
10 M Ohm ⅛ W
220 Ohm ⅛ W
+5 Volts DC
A method 100 for generating a wireless signal 71 is described in
A method 200 for processing the wireless signal 71 and controlling the motor controller 44 is described in
While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1292022||Mar 23, 1917||Jan 21, 1919||Thomas F Newman||Stevedore's truck.|
|US2996133||Apr 7, 1960||Aug 15, 1961||New Design And Dev Corp||Power attachment for appliance trucks|
|US3182835||May 13, 1963||May 11, 1965||Meyer Irel H||Powered barrel truck|
|US3499501||May 22, 1967||Mar 10, 1970||Craft Corp||Stair climbing apparatus|
|US3719247 *||Apr 7, 1971||Mar 6, 1973||R Hollis||Golf cart|
|US3896893 *||Oct 1, 1973||Jul 29, 1975||Decker Executor By Norman E||Differential torque responsive axle for small vehicles|
|US4033595||May 5, 1976||Jul 5, 1977||Floyd Mauch||Hand truck|
|US4136888||Oct 7, 1977||Jan 30, 1979||The United States Of America As Represented By The Department Of Health, Education And Welfare||Transport device for invalids|
|US4155418 *||Jun 3, 1977||May 22, 1979||Bombardier Limited||Snowmobile engine safety cut out system|
|US4706072 *||Nov 29, 1984||Nov 10, 1987||Aisin Seiki Kabushiki Kaisha||Human condition monitoring and security controlling apparatus on a road-vehicle|
|US4762193||Jan 16, 1987||Aug 9, 1988||Dorothy Margaret Levine||Motorized golf trolley|
|US4792052 *||Aug 4, 1986||Dec 20, 1988||Kabushiki Kaisha Komatsu Seisakusho||Apparatus for controlling the number of revolutions of an engine|
|US4941854 *||Nov 25, 1988||Jul 17, 1990||Sanshin Kogyo Kabushiki Kaisha||Boarding sensor and controller for small watercraft|
|US4974693||Jun 7, 1989||Dec 4, 1990||Yamaha Hatsudoki Kabushiki Kaisha||Powered three wheeled golf cart|
|US5322306||Apr 10, 1990||Jun 21, 1994||Rosecall Pty Ltd.||Vehicle for conveying trolleys|
|US5746282||Apr 12, 1996||May 5, 1998||Matsushita Electric Works, Ltd.||Power-assisted cart|
|US5749424 *||Jan 26, 1995||May 12, 1998||Reimers; Eric W.||Powered cart for golf bag|
|US6062328||Jun 10, 1998||May 16, 2000||Campbell; Jeffery D.||Electric handcart|
|US6098732||Aug 31, 1999||Aug 8, 2000||Medicart, L.L.C.||Apparatus for providing self-propelled motion to medication carts|
|US6173799 *||Oct 26, 1998||Jan 16, 2001||Honda Giken Kogyo Kabushiki Kaisha||Motor-assisted single-wheel cart|
|US6210095||Jun 4, 1998||Apr 3, 2001||Paul Hempel||Carpet loading system|
|US6474427||Apr 14, 2000||Nov 5, 2002||James William Tunnecliff||Wheeled device with different operational modes|
|US6496117 *||Mar 30, 2001||Dec 17, 2002||Koninklijke Philips Electronics N.V.||System for monitoring a driver's attention to driving|
|US20040238241||May 14, 2004||Dec 2, 2004||Mitchell Lawrence Carhart||Front wheel motor driven-golf trolley|
|US20050081670 *||Sep 15, 2004||Apr 21, 2005||Calsonic Kansei Corporation||Operating position select device for automatic transmission|
|US20070193754 *||Feb 23, 2006||Aug 23, 2007||Beckman Carl L||Linear actuated reciprocating garden HOE|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US8984685||Feb 15, 2013||Mar 24, 2015||Stryker Corporation||Patient support apparatus and controls therefor|
|US9101348||Mar 13, 2014||Aug 11, 2015||Intuitive Surgical Operations, Inc.||Surgical patient side cart with drive system and method of moving a patient side cart|
|US9308937||Mar 13, 2014||Apr 12, 2016||Intuitive Surgical Operations, Inc.||Surgical patient side cart with steering interface|
|US20120012409 *||Jan 19, 2012||Patrick Edward Turner||Power-Assist Hand Truck or Platform Cart|
|US20120242063 *||Sep 27, 2012||Carl Bruckner||Device and System for Transporting and Dispensing Cables and Wires|
|U.S. Classification||180/19.1, 180/272, 180/19.3|
|International Classification||B62B1/00, B62B5/00, B62D51/00, B62D51/04|
|Cooperative Classification||B62B2205/10, B62B5/0026, B62B5/0033, B62B1/10, B62D51/001, B62B1/002|
|European Classification||B62B5/00P, B62D51/00B, B62B1/10, B62B1/00C|
|Jul 18, 2014||REMI||Maintenance fee reminder mailed|
|Dec 2, 2014||SULP||Surcharge for late payment|
|Dec 2, 2014||FPAY||Fee payment|
Year of fee payment: 4